Between the 4th August and 2nd September two ATF Chile instructors (Rodrigo and myself!) took to the high seas onboard a Chilean pelagic longline vessel that fishes for swordfish. What was our mission? What was our objective?
Well, we were doing what the Task Force does best: conducting experiments in the use of mitigation measures that prevent seabird bycatch. We were investigating a combination of mitigation measures, at-sea and under commercial conditions with the view of measuring the efficiency of these measures and comparing the effect of seabird friendly fishing practices on target (fish) catch rates. In short, can we save the birds with current measures and will they impact the fishery?
Our work included measuring the sink rate of baited hooks to see if a modified fishing line would sink faster than the typical gear used in this fishery. The idea is, that if the hooks sink faster, the seabirds have less time to take the bait!
To do so, we had to keep in mind that some albatross species can dive down to 4 or 5 metres while many species of petrel can dive down past 10 metres. This means we have to help the fishing gear sink really quickly and out of the reach of these vulnerable birds.
We combined this with seabird counts and studies of how the birds attack hooks when we used the different kinds of fishing gear. This gives us an idea how the measures are working and to what extent they are effective solutions to seabird bycatch.
Not everything’s an experiment!
While we were aboard I also took some time to conduct at-sea observations of the seabirds that were present and those that followed the vessel. During one of these periods, I noticed a couple of the beautiful and critically endangered Waved albatross, birds that nest in the Galapagos Islands. This was the first time I had seen this species as they are not normally present this far south in Chilean waters.
I was even more surprised to find that I was recording the southern-most sighting of this species! I was able to get a couple of photos to confirm the sighting (see the picture), close to San Ambrosio Island more than 900 km off the coast of Chile (26°20’37”S, 079°53’28”W). We had to go a long way to see these birds, but it was worth it!
Working at-sea can be a real challenge sometimes but it also gives you the chance to glimpse the beauty and hidden secrets within the vastness of the ocean, his Majesty the Pacific!